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Surface plasmon resonance (SPR) sensor is one of the most viable technologies for portable and highly sensitive sensing in clinical and environmental applications. A lot of research on SPR sensors based on plasticized polyvinyl chloride (PVC) sensing layers for detection of various metal ions has been well reported, but a study on their correlation between sensing layer thickness and sensor response has been rarely done. The purpose of this study is to investigate thickness dependence of sensing layers on the response time and the sensitivity of SPR sensors based on plasticized PVC. Calcium ionophore was incorporated in the sensing layers for calcium ion detection. Our experimental results showed that thicker sensing layers exhibited higher sensitivity and wider detection range but longer response time. We discussed metal ion diffusion in plasticized sensing layers by correlating numerical calculations with experimental ones in order to understand temporal response of our SPR sensor. The response time also relied on the flow rate of calcium ion solutions, indicating that metal ion diffusion in bulk media is one of the limiting factors. [ABSTRACT FROM AUTHOR]

In this study, a theoretical parametric study on the bimetallic waveguide coupled surface plasmon (SP) resonance sensors was presented in comparison with other alternative configurations suggested to achieve a high sensing resolution. The increasing ratio of inner Ag to outer Au was found to have more drastic effect on the enhancement in the SPR curve sharpness and the sensing resolution in response to the changes in bulk and thin analytes. It was confirmed that the effect of Ag to Au ratio was incomparably superior to that observed in a simple Au/Ag bimetal approach. Remarkably, our calculation also indicated that the sensing resolution could be comparable to that of long range SP resonance configuration and even better for the detection of thin analytes as the Ag to Au ratio increased to 3.75. In addition, the great flexibility in materials selection for the dielectric waveguide and the periodic generation of waveguide coupled modes were verified and their effects were discussed. [ABSTRACT FROM AUTHOR]

This paper reports the fabrication of crystalline silicon passivated emitter rear totally diffused (c-Si PERT) solar cells with ultra-thin p-type wafers 50 µm in thickness. Co-diffusion of boron and phosphorus in a single rapid thermal processing cycle, and an Al spin-on glass post-curing process were developed to remove the boron rich layer which is detrimental to c-Si solar cells. Co-diffusion was carried out with spin-on diffusion sources using boric acid and a P spin on dopant for simple and cost-effective emitter and back surface field (BSF) formation processes. The fabricated ultra-thin c-Si PERT cell featured an open circuit voltage (Voc) of 0.575 V, a short circuit current density (Jsc) of 35.8 mA cm−2, a fill factor of 0.725, and a power conversion efficiency of 15.0%. The efficiency has improved by 2% compared with the standard structure cell with Al-BSF using thin evaporated Al 2 µm in thickness. Along with cell output parameters, the flexural strength and critical bending radius were measured by a four point bending test, and the results showed that the solar cells with thinner rear Al electrodes are more applicable for a flexible solar cell device. [ABSTRACT FROM AUTHOR]

Optimally designed Si nanostructures are very effective for light trapping in crystalline silicon (c-Si) solar cells. However, when the lateral feature size of Si nanostructures is comparable to the junction depth of the emitter, dopant diffusion in the lateral direction leads to excessive doping in the nanostructured emitter whereby poor blue responses arise in the external quantum efficiency (EQE). The primary goal of this study is to find the correlation of emitter junction depth and carrier collection efficiency in nanostructured c-Si solar cells in order to enhance the blue responses. We prepared Si nanostructures of nanocone shape by colloidal lithography, with silica beads of 520 nm in diameter, followed by a reactive ion etching process. c-Si solar cells with a standard cell architecture of an Al back surface field were fabricated varying the emitter junction depth. We varied the emitter junction depth by adjusting the doping level from heavy doping to moderate doping to light doping and achieved greatly enhanced blue responses in EQE from 47%–92% at a wavelength of 400 nm. The junction depth analysis by secondary ion mass-spectroscopy profiling and the scanning electron microscopy measurements provided us with the design guide of the doping level depending on the nanostructure feature size for high efficiency nanostructured c-Si solar cells. Optical simulations showed us that Si nanostructures can serve as an optical resonator to amplify the incident light field, which needs to be considered in the design of nanostructured c-Si solar cells. [ABSTRACT FROM AUTHOR]

We demonstrate the fabrication of shallow Si nanopillar structures at a submicron scale which provides broadband antireflection for crystalline Si (c-Si) solar cells in the wavelength range of 350 nm–1100 nm. The Si random nanopillars were made by reactive ion etch (RIE) processing with thermally dewetted Sn metals as an etch mask. The diameters and coverages of the Si nanopillars were adjusted in a wide range of the nanoscale to microscale by varying the nominal thickness of the Sn metals and subsequent annealing temperatures. The height of the nanopillars was controlled by the RIE process time. The optimal size of the nanopillars, which are 340 nm in diameter and 150 nm in height, leads to the lowest average reflectance of 3.6%. We showed that the power conversion efficiency of the c-Si solar cells could be enhanced with the incorporation of optimally designed Si random nanopillars from 13.3% to 14.0%. The fabrication scheme of the Si nanostructures we propose in this study would be a cost-effective and promising light trapping technique for efficient c-Si solar cells. [ABSTRACT FROM AUTHOR]